/*
 * Copyright:  2018 smarabbit studio.
 *
 *  Licensed under the Confluent Community License; you may not use this file
 *  except in compliance with the License.  You may obtain a copy of the License at
 *
 *  http://www.confluent.io/confluent-community-license
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OF ANY KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations under the License.
 *
 *  @作   者： 黄开晖 (117227773@qq.com)
 *  @日   期:  2021年6月2日
 */
package com.massyframework.beanskin.runtime.framework.installing;

import java.util.Objects;

import javax.script.ScriptEngine;
import javax.script.ScriptException;

/**
 * 基于Nashron的表达式
 * @author huangkh
 *
 */
final class ScriptExpression<T> implements Expression<T> {

	private ScriptEngine engine;
	
	/**
	 * 构造方法
	 * @param engine  {@link ScriptEngine}
	 */
	protected ScriptExpression(ScriptEngine engine) {
		this.engine = Objects.requireNonNull(engine, "\"engine\" cannot be null.");
	}

	@Override
	public void setVariable(String name, Object value) {
		this.engine.put(name, value);
	}

	@SuppressWarnings("unchecked")
	@Override
	public T evaluate(String text) throws ScriptException{
		Object result = this.engine.eval(text);
		return (T)result;
	}
}
